Brake-applying apparatus



Feb. 26, 1929.

C. S. BUSHNELL BRAKE APPLYING APPARATUS Original Filed March 20, 1925 n I u I n I I n I,

Equal Res MR MR 3 A isz szo s Timing Res.

C P 0 z/// l H Patented Feb. 26, 1929.

UNITED STATES PATENT OFFICE.

. CHARLES S. BUSHNELL, OF ROCHESTER, N YORK, ASSIGNOB TO GENERAL RAILWAY SIGNAL COMPANY, OF ROCHESTER, NEW

tome.

BRAKE-APPLYING APPARATUS.

Original application filed March 20, 1925, Serial in. 10,931. mv'ideaana this application filed April 7,

1987. Serial No. 188,898.

This invention relates to brake applying apparatus for railway trains, and more particularly to control apparatus adapted for controlling the brakes of such trains either for effecting a brake application for various reasons some of which'will now be given. If an automatic brake application is made by suitable train control apparatus it is essential that the engineer should not be permitted to annul such a brake applicationv by recharging the brake pipe and for this reason the engineers' brake valve itself is preferably moved as far as the lap'position at least. if a predetermined reduction only in brake pipe pressure is to be madethe same device is preferably used so that a second predetermined reduction is not made on top of the first predetermined reduction, and further it is desirable to effect an automatic brake applica tion and manual brake application y the same device so that, by reason of the fact that since automatic brake applications only seldom occur, and if the same device is used for effecting a manual and an automatic ap lication the mechanism does not stand i le as much but is operated repeatedly by theengineer when making a manual brake application. It hasbeen experienced in the application of automatic train control to railways that a two-stage brake application is much safer in preventing break-in-tw0s and buckling of trains when an automatic brake application is made. One of the problems confronted in designing brake control mechanism for making a two-stage brake application is the determination of the'period of time intervening between the two stages. In order to discuss this further it isconsidcred advisable to review briefly the operation of the usual air brake system.

In the usual air'brake system a service brake application is effected by venting the usual equalizing reservoir to a predetermined extent and usually to that pressure at which the auxiliary reservoir pressure equalizes with that of the brake cylinder on an average car. This reduction in equalizing reservoir pressure causes the equalizing discharge piston valve located directly under the engi- .sure in the brake pipe an neers brake valve to open and discharge brake pipe pressure until the brake pipe pressure has been-reduced to that of the equalizing reservoir pressure. This equalizing discharge piston valve is designed so that this valve gradually closes as the pressure in the brake pipe approaches that of the pressure on the other side of the piston, namely, the equalizing reservoir pressure, consequently the blowing off of air is tapered, so to speak, and the rate of dischar e is not in proportion to pressure only but is e endeiit on the res- (i the opening abrded by this equalizing discharge piston valve. Since the flow of air from the brake pipe through this equalizing discharge piston valve is tapered asvjust explained, a twostage brake application. even though the second stage starts immediatelyafter the first stage has been completed, is difiere'n't from a single stage brake application effecting the saine reduction in brake pipe pressure; this being true because in the two-stage brake application the pressure above the equalizin discharge piston is reduced say half as muc in each stage, so that two tapering discharge periods transpire, whereas if a single reduction is made a single taper discharge period transpires. Obviously, the effect of two light tapering discharges of air from the brake pipe will have a different efl'ect on the triple valves of the cars of the train than will. one heavy taperin discharge. this discussion in min that the second stage reduction might even be started before the first reduction. stage has been completed, and stillefi'ect a brake application that is difierent from a single stage brake ap lication.

cone 0 the reasons for employing a twostage brake application is-that the slack between carslshall first be taken up before a heavy brake application takes place, so as to avoid buckling of the train; and since the taking up of the slack depends upon the length of the train, the grade of the track, the speed of the train and the like, it is diflicult to determine how the two reductions of a twostage application should be spaced; this same thin .also being true of break-in-twos. Net, it is iflicult to determinedefinitely just what kind of a two-stage brake application should be made to suit the various conditions encountered in practice.

Bearing it readily appears In accordance with the present invention it is therefore proposed to either start the second reduction a predetermined time after the first reduction has been started, which may be varied according to the length of the train and the particular grade on which thetrain is traveling at the time, to have this time fixed for all conditions or to have the second stage reduction start immediately after the first 'is in the release or running position but not when in the lap position; to provide. automatic means-for operating the usual engineers brake valve and this supplemental valve to the service position and during such operation unlatch the handle of the engineers brake valve so that the engineer can not prevent the automatic operation taking place and also to avoid injury due to automatic movement of such handle; and to provide means for connecting the two reduction reservoirs together asuitable period of time after an automatic brake application is initiated.

As a further object of the present invention it is proposed to provide means for penalizing the engineer if he does not anticipate the automatic means in starting a brake applica tion himself or does not properly control the train. I

Other objects, purposes and characteristic features of the invention will in part be pointed out in the description hereinafter and in art be obvious from the drawings.

n describing the invention in detail reference will he made to the accompanying drawings in which F i 1 shows an embodiment of the invention including brake applying mechanism in which the second stage reduction is started a definite period of time after the first reduction is started, this period of time being adjustable for the particular train and grade, together with means for penalizing the engineer if he does not properly control his train Fig. 2 is a section taken on the line 1515 F Tl; ig, 3 is a section taken on the line iii-18 Fig. 1; and

4 shows the ports of the supplemental service exhaust valve used in. the, arrangement shown in Fig. l.

lln describing the invention the usual en gineers brake valve as mod? toge her with the actuator and supple;- =ntal service exhaust valve will not be descris-e-d detail,

mosses since reference to the parent application, in which such description is made, may be had.

This application is a division of my prior application Ser. No. 16,937 filed March 20, now Patent No. 1,628,45 dated May 10,

Referring to Fig. 1 the usual engineers brake valve 1, having a modified form of cap member or main frame 4 including the notched sector 5 projecting horizontally therefrom into which the latch plunger associated with the engineers'brake valve handle 7 may engage, has been shown. On the flange just mentioned are bolted the cylinders 10 and 11 of the automatic brake valve actuator. It should be noted that the cylinders 10 and 11 are of difierent diameter so that difierent forces are exerted by the pistons contained therein. Both of these cylinders normally contain main reservoir pressure, the small one of which is directly connected to main reservoir ressure existing on top of the rotary valve 0 the engineers brake valve..- The large cylinder is normally, when the electro-pneumatio valve EPV controlled by suitable train control means controlling the contacts 82 and '82 is energized, connected to main reservoir pressure through pipes 83 and 69, but is vented to atmosphere through pipe 85 when the device EPV is ole-energized, as a result of which the piston in the small cylinder operates the usual rotary valve and an auxiliary valve to-a brake applying position. In the top part of the actuator and below the cover 24 is contained a supplemehtal rotary valve 22 (see Fig. 4*.) which is operatively connected to the usual rotary valve and is always moved therewith thus supplemental valve contains an opening 76 and a cavity T7, and is seated on a valve seat containing openings 70, 71 and 72. The opening is connected to the equalizing reservoir 80, the openin%71 is connected to, the reduction reservoir 1 and the opening 72 is connected to atmosphere. The opening 7 6 extends through the supplemental valve 22 and is under any position of the engineers brake valve" handle in communication with the opening 70, so that the valve 22 is held against its seat by equalizing reservoir pressure. The cavity 77 1s so. located and of such size that it connects the equalizing reservoir 80 to the reduction reservoir R when the engineersbrake valve handle is in the service or energizing position and connects the reduction reservoir R to the atmosphere port 72 when the engineers brake valve handle is in the release, running or holding position, and blanks the reduction reservoir opening 71 when the engineers brake valve handle is in the la position. The brake valve actuator including cylinders 10 and 11 is so constructed that the engineers handle 7 is unlatched and disconnected so far as operation of the main rotary valve and the auxiliary toward the release position by such handle is concerned when the actuator operates these valves to make an automatic brake application, but this handle is always in condition to operate these valves to the energizing position. For a detailed description of the brake valve actuator and the various passages associated with the auxiliary valve reference should be had to the parent patent above mentioned.

As heretofore intimated, it is contemplated in accordance with the present invention to penalize the engineer if he does not properly control his train,- or putting it another way, reward the engineer if he controls his train properly. In the application of train control to existing railways. and signalling systems, one theory of safeguarding the train to the maximum extent is based on the idea of maintaining the safety afforded by the engineer without automatic train control and add to this safety that afforded by the automatic train control mechanism. If train control is added without the provision of means for stimulating the vigilance of the engineer, he is apt to rely too much on the automatic apparatus, especially after he has convinced himself that it is very reliable; and if he does rely on the automatic apparatus, the automatic apparatus is really a substitute for the engineer and is not a supplemental and additional safeguard to that of the engineer.

It is therefore proposed in accordance with the present invention to penalize the engineer if the automatic brake applying means functions and the engineer has not already started a bonafide brake application, which may be either a single or multiple stage full service brake application. Since the brake applicationmade by the engineer need only be a reduction to give a full service brake application it is unnecessary, and a waste of air, to allow the automatic apparatus to make a further reduction in brake pipe pressure after the engineer has already started or completed the necessary reductions to give a full service brake application, and in accordance with the invention shown in Fig. 1 if automatic operation of the actuator takes place after the engineer has already made a full service brake application no further venting of the brake pipe takes place. Also, in this event the engineer is rewarded, so to speak, for having made a brake application before the automatic apparatus began functioning, which reward in the arrangement shown consists in the engineers ability to release the brakes after the train control mechanism again assumes its normal condition and recloses contacts 82 and 82 without necessarily bringing the train to a full stop.

lVhen two engines are used in tandem to pull a train, which is commonly called double heading, the double heading cock, contained in the pipe connecting the brake pipe to the engineers brake Valve, of the second engine must be closed. Also, the second engine when double heading, especially in certain types of train control systems, can not receive control influences inductively from the trackway and therefore is not subjected to automatic train control, so that,'it is desirable to cut out the automatic control for the actuator of the second engine under this condition. Since it is necessary to operate the cut-out cock, which is usually located in the cab, when double heading, andstill fix it so that the engineer cannot avoid an automatic brake application when single heading by shutting off this cock when the actuator begins to operate, these two cocks (cut-out and double heading cock) are preferably mechanically interlocked, and are locked by the same padlock,- the key of which is preferably held by the conductor of the train.

In addition to the apparatus already mentioned Fig. 1 shows the usual air compression governors 122 which control the main reservoir pressure by controlling the flow of steam to the air compressors which are used in connection with the usual air brake system. These governors 122 are connected to the engineers brake valve through the excess pressure head or governor pipe 123 in the usual way, this pipe 123 through a port in the rotary valve-of the engineers brake valve being connected to main reservoir pressure so long as the brake valve is in the release, running, or holding position, and being con nected to atmosphere when the brake valve is in the lap or service position. The cavity for venting the pipe 123 to atmosphere as ust explained is ordinarily not present in an engineers brake valve but is added in accordance with the present invention so that when this brake valve is moved to the lap or service position the excess pressure head pipe 122 is vented to atmosphere.

In Fig. 1, there has also been shown a pneumatically operated timing means for opening a circuit a predetermined time after the engineers brake valve has been operated to the service position automatically. This timing mechanism TM comprises a timing reservoir 130, which is connected to the excess pressure head governor pipe 123 through pipes 131v and 132. In order to adiustably fix the rate of discharge of pressure from the timing reservoir through the excess pressure head pi pc 123 and the ports and cavities in the cngi 'neers brake valve to atmosphere, a graduated restricted opening is provided by the adjustable valve 133. This valve contains a valve plug 134 adapted to fit in a tapered opening, the position of which may be changed by turning the knurled head 135 to which apointer or indicator 136 is fastened. This indicator moves over a dial 137, which dial may be graduated in any suitable way. In

practice, since long trains require more time to get the slack between cars adjusted, it is considered expedient to graduate this dial in the length of the trainby marking thereon the number of cars so that the indicator may be moved to a number corresponding to the number of cars which are being pulled at the time. However, if it is considered expedient to take into consideration the average or particular grade over which the train is moving, adjustment for this purpose may be incorporated on this dial also. This timing mechanism also includes a cylinder 140 having a piston 141 therein, which piston is normally maintained in the position shown by main reservoir pressure'confined in the timing reservoir 130, thus maintaining the contact 142 in a closed position against the action of the compression spring 143. It readily appears that when the pressure in the reservoir 130 has been reduced to a predetermined pressure, depending upon the strength of the spring 143, the contact 142 will move away from the stationary contacts indicated by. arrows, thereby opening the circuit for the electrically operated valve EV.

It should be noted that there is shown a double cockDC having a stem 150 therein to which is fastened the handle 151, this stem being slightly tapered and held in place by the compression spring 152. The right hand portion of this cock, the cross section of which is shown inFig. 2, is the usual double heading cock, which is normally open when the handle 151 as shown is locked by the padlock 153, and this cock blanks the connection between the engineers brake valve and the brake pip-e when it is turned to its abnormal position. The left hand portion of this dou ble cock DC normally connects the device EIV to the large cylinder of the actuator as clearlyshown in Fig. 3, and this cock when turned to its abnormal position connects the main reservoir MB to the large cylinder of the actuator as is obvious from Fig. 3 when the valve stem is turned inth-e counter-clockv wise direction through substantially 90 degrees to its abnormal position.

' Although a padlock 153 has been shown for locking the double cock DC it is to be understood that this look may be omitted if desired, especially bearing in mind that the Interstate Commerce Commission at present does not permit the double heading cock to be locked. Also, this double cock DC whether locked or not may be located so as to be accessible only from the ground, in which event the engineer cannot misuse the double heading cock to prevent an automatic brake application when not double heading.

In order to inflict the penalty heretofore mentioned, which in the particular arrangement shown consists of means accessible only from the ground, the engineer is required to mosses alight to the ground and push the reset push button PB and restore the penalty relay PR, this push button PB being accessible from theground only. This penalty relay PR under normal clear traflic conditions is energized through a stick circuit including its own contact 156, which circuit may be traced as follows :beginning at the terminal B of a suitable source of energy, wire 157, contacts 82 operated by the automatic train control apparatus and which open at the same time contacts 82 open, wire 158, front contact 156 of the penalty relay PR, wires159 and 160, winding of the penalty relay PR, wire 161 to the common return wire G connected to the other terminal of said source of energy. With this penalty relay PR energized, the electro-p-enumatic valve EPV'is also energized through the following circuit :-beginning at the terminal B, wire 162, contact 82, controlled by the train control mechanism, wire 163, winding of the device EPV, wire 164, front contact 165 of the penalty relay PR, wire 166, normally closed contact 167 of the push .button PB, wire 168 to the common return wire C. From this latter circuit it will be noted that the device EPV can not be energized when the penalty relay PR is in its de-energized condition; also with .the penalty relay PR once de-energized it can not be picked up without first bringing the train to a stop.

It is desired to be pointed out at this time that the supplemental valve 22 forming part of the actuator shown in Fig. 1, is slightly different from that shown in some of the figures in the parent patent. The supplemental valve 22' (see Fig. 4) does not vent the equalizing reservoir to atmosphere through the cavity 7 7 when theengineers brake valve is in the lap position as it does in the various systems shown in the parent application (see Fig. 7 showing the lap'position of the sup plemental valve of the previous systems). In the system shown in Fig. 1, the supplemental valve 22has its cavity 77 preferably so cut that the reduction reservoir is only vented to atmosphere when thevalve is moved toward the release position beyond the lap position, and preferably at a point before it reaches the holding position, that is, it is proposed to provide an additional position of the engineers brake valve between the lap and the holding position in which the reduction reservoir R may be vented to atmosphere. If desired, however, this venting of the reduction reservoir may take place in the holding position, the object being to permit the engineer to partially vent the reduction reservoir to atmosphere by moving the engineers brake valve slightly to the'left of the lap position without releasing the brakes of the train, which release of brakes takes place rather slowly if the engineers brake valve is moved to the holding position.

' shown in Fig.

Manual operation (Fig. 1).

In considering the operation of the system 1, let us assume that the enginecr is aware of the fact that an automatic brake application is just about to be effected by the automatic apparatus, and that he wishes to anticipate this automatic application and thereby avoid the penalty, which penalty consists in restoring the penalty relay PR by aligh ting to the ground and depressing the push button PB, only accessible from the ground. Let us further assume that the engineer considers it necessary to make a multi-stage brake application, in order to' bunch the slack between cars properly before the actual full service brake application takes place, and in making a multi-stage brake application moves his valve handle to the service position and leaves it there until the equaliz'ng reservoir pressure has been reduced about eight pounds after which he returns the handle to the lap position. By rea son of the modified construction of the supplemental valve 22 as shown in Fig. 4, from that shown in parent a plication the reduction reservoirs R and 2 are not discharged to atmosphere while his handle is in the lap position. With this reduction of eight pounds in equalizing reservoir pressure, the rqualizing discharge piston valve, within the engineers brake valve casing 1, begins to function and causes brake pipe pressure to be discharged through the chamber 95 and the usual service exhaust fittin 31. This causes the contacts 120 to close so on as brake pipe pressure is discharging throug this equalizing discharge piston valve. It is of course understood that the diaphragm 97 is pressed outward to close contact 120 if brake pipe air is exhausted through port 31 at a predetermined rate. In this connection it should be noted that while the engineers brake valve was in the service position, the stick circuit for the, penalty relay PR was com leted through: a'circuit including contact-s 1 0 opcratcd by the handle of the engineers brake valve, which contacts 17 0 are closed so long as this valve is in the service or emergency po- I sition, which circuit is readily traced in the drawings; and that the stick circuit of the penalty relay PR was closed through a branch circuit including the contacts 120 which contacts are closed so long. as brake pipe pressure is dischargin from the brake pipe through the exhaust tting 31 due to the consummation of a brake application. In other Words, if either the engineer has his brake valve in a brake applying position, or brake pipe pressure is discharging from the service exhaust fitting 31, the penalty relay PR is hold up independently of the contacts 82 controlled by the train control mechanism. The net result is, the engineer may make any number of successive reductions in equalizing reservoir pressure without dropping the penalty relay PR in spite of theopening of contacts 82, so long as he has either got his handle in a brake applying po} sition or brake pipe pressure is discharging from the service exhaust fitting 31. In this connection it is desired to be pointed out that, although contacts 120 are also closed when pressure fluid discharges from the exhaust fitting due to an automatic application, the closure of these contacts 120 under this condition will not revent the droppingof penalty .relay PR,%ecause they close after this relay has already dropped due to opening of contacts 82; further contacts 170 do not close at all in response to an automatic application. From this it will be noted, that the engineer is required to leave his valve in the service position after having made several successive reductions in equalizing reservoir pressure, so as to eventually maintain contacts 17 0 closed and maintain the penalty relay PR energized to avoid the penalty. With the engineers brake valve finally left in the service position a full service brake application will take place because contacts 53 operated by the engineers brake valve will be opened under this condi- ;tion and the reduction reservoirs Rand R will equalize in pressure with theequalizing reservoir pressure, the volumes of these reservoirs being so chosen that a full service brake application results if they are all connected together.

From the above it appears that if an automatic brake application had taken place during any time while the engineer was making a multiple stage manual application the o ing of contacts 82 would ave de-energlzed the device EPV and effected an automatic brake application as presently will be described, but by reason of the engineers anticipation in starting a brake ap lication the opening of contacts 82 won d not have dropped the penalty relay PR, because this penalty relay PR was at all timesheld up by one or the other of the two supplemental or branch circuits including contacts 170 and respectively, so that in the structure shown the penalty relay PR is maintained up after the engineer startsand carries out 11 either a single or multi-stage brake application.

I Automatic operation (F ig. 1).

Let us now assume that the engineer is not 120 vigilant, is incapacitated or is asleep, and that an automatlc brake application is initiated by opening of contacts 82 and 82 by suitable train control mechanism. The opening of contacts 82 breaks the stick circuit for 1 :the penalt relav PR and the droppingof this penalty re ay PR by reason of openin of its opens the circuit or the front contact device EPV, this EPV circuitalso being opened at another point by the contacts 82,

"electro-pneumatic valve, closed after the,

the scope of the present invention or the idea of means underlying the same.

What is desired to be secured by Letters Patent is 1. In a braking systemv for railway trains of the type in which the brake pipe is normally charged and in which a brake application is efi'ected if brake pipe pressure is reduced, the combination withan .engineers brake valve of the type described and usually employed in systems of this type having an excess pressure head governor pipe which is vented if said engineers brake valve is placed in the service brake applying position, a pneumatic timing device connected to said pressure head pipe, said timing device being constructed so as to perform a function a definite period of time after said pipe is vented. q

2. In a b aking system for railway trains of the type in which the brake pipe is normally charged and in which a brake application is-etfected if. brake pipe pressure is reduced; in combination an equalizing reservoir, and a reduction reservoir; of an engineers brake valve of the construction usually employed in systems of this kind but modified by having cavities and port-s for connecting the equalizing reservoir to the reduction reservoir when said brake valve is in the service brake applying position, and for connecting said reduction reservoir to atmosphere when the brake valve is in the normal position; a handle for operating said valve; automatic means for simultaneously operatively disconnecting said handle from said valve and operating said valve to the service positionj a second reduction reservoir; an eiectro-pneumatic valve in a pipe connecting said reduction reservoirs which valve if energized isolates said reservoirs; a contact in the circuit for energizing said lapse of a predetermined interval'of time after said automatic means is rendered active, the period of time which lapses between the instant when said automatic means is rendered. active and the closure of said contact being adjustable to effect the proper brake application for the particular train the engine is pullin at the time.

3. In a bra e applying apparatus for automatic train control systems used on'trains,

employing a braking system of the ty in which the brake pipe'is normally chargedfmd in which venting of the brake pipe effects a brake, application, mechanism initiated automatically by suitable train control mechanism comprising,

means for effecting a predetermined reduction in brake pipe pressure upon'actuation of said control mechanism, and means including a time element device for effecting a lurther reduction in brake pipe ressure a predetermined period of time a er said the combination of first mentioned means is actuated, said time element device being adjustable to efiect the proper spacing between the two sta es of brake pipe pressure reduction "for the ength of the particular train the engine is pulling at the time. i

4. In a brake applying apparatus for automatic train control systems used on trains employing a braking system of the type in which the brake pipe is normally charged and in which venting of the brakepipe efiects a brake application, the combination of mechanism initiated automatically by suitable train control mechanism comprising, means for effecting a predetermined, reduction in brake pipe pressure upon actuation of'said control mechanism, and means including a time element device for efiecting a further reduction in brake pipe pressure a predetermined period of time after said first men-' tioned means is actuated, said time element device being changeable and calibrated so as to be readily adjustable to effect the proper two stage reduction for the length of the particular'train the engine is pulling at the time. 1

5. A brake valve actuator constructed so as tobe readily superimposed upon an engineers brake valve of the usual comprising a small cylinder having a piston therein and directly connected to the main reservoir pressure supply contained on top of therotary valve of-such engineers brake valve, a'large cylinder having a piston therein acting inopposition to the piston of the construction,

small cylinder and normally connected to main reservoir pressure, whereby if pressure is vented from the large cylinder said actu-" ator is o erated, an electro-pneumatic' valve for supp ying and removing pressure from said large cylinder, and a cut-out cock normally connecting said large cylinder to said electro-pneumatic valve and which if operated to its abnormal position connects said large cylinder to said small cylinder.

6. A brake valve actuator constructed so as to be readily superimposed upon an engineers brake valve of the usual construction comprising a small cylinder having a piston therein and directly connected to main reser: voir pressure contained inthe space on top of the rotary valve of such engineersbrake' valve; a large cylinder having a piston therein acting in opposition to the piston in the small cylinder and normally connected to imain reservoir pressure; whereby if pressure is vented from the large cylinder said actuator is operated; an electro-pneumatic vvalve for supplyin and removing pressure from said large cy inder; and a'cut-out cock, mechanically connected to the usual double heading cock contained in the brake pipe connection leading to said engineers brake valve, normally connecting said large cylinder to said electro-pneumatic valve and which if said double heading cock is operated to the double heading position said cut-out cock connects said large cylinder to main reservoir pressure. t

7 A brake valve actuator constructed so as to be readily superimposed upon an engineers brake valve of the usual construction comprising a SmalPcylinder having a piston therein and directlyconnected to main reservoir pressure contained in the space above the rotary valve of such engineers. brake valve; a large cylinder having a piston therein acting in opposition to the piston in the small cylinder and normally connected to main reservoir pressure; whereby if pressure is vented from the large cylinder said actuator is operated; an electro-pneumatic valve for supplying and removing pressure from said large cylinder; a cut-out cock, mechanically connected to the usual double heading cock contained in the brake pipe connection leading to said engineers brake valve, normally connecting said large cylinder to said electro-pneumatic valve and which cut out cock if said double heading cock is operated to the double heading position connects said large cylinder to .main reservoir pressure; and a lock for locking said double heading cock.

8. A brake valve actuator constructedso as to be readily superimposed upon an engineers brake valve of the usual construction comprising a small cylinder having a piston therein and directly connected to main reservoir pressure contained in the space above the rotary valve of such engineers brake valve, a large cylinder having a piston therein acting in opposition to the piston in the small cylinder and normally connected to main reservoir pressure, whereby if pressure is vented from the large cylinder said actuator is operated, an electro-pneumatic valve for supplyin and removing pressure from said large cy inder, and a cut-out cock normally connecting said large cylinder to said electro-pneumatic valve and which if operated to its abnormal position connects said large cylinder to said small cylinder, and a seal for locking said cut-out cock into its normal position.

9. In an automatic train control system the combination with the usual air brake system including the usual engineers brake valve and a normally charged brake pipe and wherein it the hrake pipe is vented to a predetermined extent a full service brake application is efi'ected, means superimposed upon said engineers brake valve and effecting such predetermined reduction only in brake pipe pressure if said engineers brake valve is moved to and left in the brake applying position, means for automatically applying the brakes, means-for penalizing the engineer if the brakes are automatically applied, and means for suppressing such penalty if the ensaid engineers brake valve for effecting such predetermined reduction only in brake pipe pressure 1f sald engineers brake valve is moved to and lett 1n the brake applying position, means for automatically applying the brakes, means for penalizing the engineer if the brakes are automatically applied, and means for suppressing such automatic brake application if the engineer places his engineers brake valve in the brake applying position. before an automatic brake application is initiated and keeps the brake valve in such position.

11. Brake applying apparatus for air brake systems of the type in which the brake pipe is normally charged with fluid pressure, and wherein venting of the brake pipe to a redetermined extent effects a full service brake application; in combination with the usual brake pipe and a main reservoir containing fluid pressure; an engineers brake valve having a running, a lap and a service position, for charging the brake pipe from said mainreservoir and venting said brake pipe to atmosphere; and of means associated with said brake valve whereby a multistage brake application may be made by repeated movements of said engineers brake valve between the service and lap positions permitting venting of the brake pipe to a redetermined extent only, and whereby i during such repeated movements the valve is moved to a position between the running and lap position the brake pipe will be vented to a greater extent.

12; Brake applying apparatus for air brake systems of the type wherein the brake pipe is normally charged and wherein venting of the brake pipe causes an application of thebrakes, the combination with a manually'operable valve having ports and passages whereby movement of said valve to different ositions may efiect charging or venting 0 said brake pipe, and means associated with said valve whereby if said valve is moved back to a lap positiona plurality of times a multistage manual brake applica tion is made by venting of the brake pipe to a predetermined extent only but if the valve is moved slightly beyond the lap position upon its return from a brake applying position and is thereafter moved to the brake applying position the brake pipe is vented to a greater extent.

predetermined reduction only in brake 13. In an air brake system of the normally charged brake pipe type, the combination with an engineers brake valve for venting and charging the brake pipe to effect ,an application and a release of the brakes respectivel and means superimposed on said engineers brake valve wherebfi if this valve is repeatedl moved'toa bra e, applying si-- tion and ack to the lap position manua 1y a 1 e pressure is madeand which includes m aiis whereby a further reduction in brake pipe pressure may be made by the engineer without placing the engineer s brake valve in the emergency position. 7

14. Automatic means for effecting a brake application suitable for the train of a' predetermined len h, and adjustable means for changing the-c aracter of brake application made by said automatic means which if adjusted to a position corresponding tothe length of the train will cause said automatic means to effect the desired character of brake application.

15. In an air brake system of the 'normally charged brake pipe type, ,the combination with" an engineer s brake valve having a brake pipe'chai'gin a brake pipe venting and a lap position, an means superimposed on said engineers brake valve w ereby if said valve is moved to a venting position the brake ipe is vented to a predetermined extent only But if said valve is then momentarily moved .with an engineers bra position beyond the la but not actuall to t e charging position an is thenmove to the venting position the brake pipe is further vented;

16. In an air brake system of the normally charged brake pipe t pe, the combination e valve having a retoward the chargin lease, running, lap, position in the order to the service position the brake pipe is vented to a redetermined extent only; and other means or permittin the reduction limiting means to effect-furt er reduction of brake pipe pressure with the valve in the service p0s1t1on which is rendered effective if the valve is moved momentarily to a position between the running and lap position.

17. In an air brake system of the normally charged brake pipe type, ihe lpon bination e Va ve avmg a reservice and emergency given reduction llmit mg means efi'ectlve if said valve is moved moved back to the service position the brake Y pipe is further veil lted. f I at n testlmon w ereo a m CfiARLES S, BU 

